A transmission chain which reduces friction on a chain guide, has been well known. In such chains by curving a back surface of a link plate in accordance with the curvature of the chain guide, the bearing pressure of the chain, generated when the chain slides on the chain guide, was made small (see for example Japanese Laid-open Patent Publication No. Hei. 10-132038).
Namely, as shown in FIG. 4, such a transmission chain 500 is comprised of bushings 540 press-fitted in a pair of inner link plates 520 and connecting pins press-fitted in a pair of outer link plates, and passing through the bushings 540 in a loosely fitted state.